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Re: curl_multi_timeout and the multi_socket API

From: Daniel Stenberg via curl-library <>
Date: Mon, 5 Apr 2021 22:43:09 +0200 (CEST)

On Mon, 5 Apr 2021, Henrik Holst wrote:

> And this particular run with 1ms did not lead to 100% cpu, it was when curl
> gave me 0ms as timeout as the last timeout which lead me to call
> curl_multi_socket_action() every 0ms, which turned it into a busy wait loop
> and hence the 100% cpu. Shouldn't curl return -1 as infinte timeout instead
> there since it's waiting for read on a connected socket (after having sent
> the request in full) with no defined CURLOPT_TIMEOUT?

0 means that there's a timeout pending that libcurl wants to take care of at
once so then it can't return -1 since -1 means no timeout at all.

So no, it cannot return -1 when it means 0.

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Received on 2021-04-05